BD-2/GPS组合导航系统选星算法及定位分析

摘要

To resolve the conflict between positioning accuracy and rapid positioning when using combined satellite navigation system,a new algorithm for choosing visible stars is presented.The algorithm combines visible satellite elevation angle with genetic algorithm,and takes GDOP calculation model as the fitness function in genetic algorithm to judge the quality of solutions,so as to achieve the effect of rapid positioning.Through the comparison of GDOP and the running time acquired by this algorithm and the method of optimum geometric dilution of precision,it is found that the method of geometric dilution of precision achieved by this method is closer to the optimal value,and the computing time of the satellite selection algorithm is reduced.Data analysis shows the advantages of the algorithm in the aspect of realtime performance and feasibility.%为解决组合导航系统定位精度与快速定位之间的矛盾,提出一种新的选星算法.该方法将可见卫星仰角与遗传算法相结合,以几何精度因子(GDOP)计算模型作为遗传算法中判断解优劣的适应度函数,从而达到快速定位的效果.将应用该方法所得的GDOP和算法运行时间与应用最佳GDOP算法计算所得的相应结果进行对比,发现采用该方法得到的GDOP接近最优值,而且选星算法计算时间减少.实验数据分析证明该方法在实时性和可行性方面的优越性.